部分相干矢量光场经生物组织散射及重构散射物结构信息的应用研究

Due to its important application value in optical communication, biomedicine, remote sensing and detection, the research on the scattering of light wave through the medium has rapidly become a current multi-disciplinary cross-frontier research hotspot. This project focuses on the weak scattering of partially coherent vector optical field upon a medium, and the scattering medium is extended to biological tissues with continuous random distribution for the first time. In this project, we mainly discuss the weak scattering of partially coherent radially polarized light field, partially coherent azithmuthlly polarized light field, and stochastic electromagnetic vortex light field by the biological tissue with the distribution of the Whittle–Matérn index. The statistical optical properties of the scattered field including the distributions of spectral density, spectral coherence, and spectral polarization are examined. Some interesting phenomenon, such as the scattering field’s spectral movement (including red shift and blue shift), spectral line width variation, and producing spectral switch under certain conditions are analyzed. The structure information of biological tissue can be reconstructed by measuring the parameters of light field scattered by biological tissue. The change of momentum flow in scattered light field will be explored, which provides a useful reference for optimizing the optical micro-control system. This study will further enrich the weak scattering theory of vector light field, and the research results are expected to find applications in areas such as tissue optical diagnosis, tissue microstructure detection, pathological tissue detection and identification, and to establish a useful platform for the basic research of scattering application.

光波经介质散射研究因为在光通信、生物医学、遥感，及检测等领域具有重要的应用价值而迅速成为当前多学科交叉前沿研究热点。本项目拟围绕部分相干矢量光场经介质弱散射这一主题，首次将散射介质拓展到具有连续随机分布的生物组织。重点探讨部分相干径向偏振光场、部分相干角向偏振光场，及随机电磁涡旋光场经过具有Whittle–Matérn族折射率关联函数分布的生物组织的弱散射。研究散射场的光谱密度、光谱相干度，及光谱偏振度等统计光学特性；分析散射场的光谱移动（包括红移和蓝移）、光谱线宽度变化，及一定条件下产生光谱开关等有趣现象；通过测量经生物组织散射后的光场参量以重构生物组织的结构信息；探讨散射光场的动量流变化，为优化光学微操控系统提供有益参考。该项研究将进一步丰富矢量光场经介质的弱散射理论，研究结果可望在组织光学诊断、组织微观结构探测、病变组织探测及识别等领域获得应用，并为散射应用基础研究建立有益平台。

本项目围绕“部分相干矢量光场经生物组织散射及重构散射物结构信息的应用研究”这一主题，开展了以下几个方面研究：1)将散射光源拓展到多色部分相干径向偏振光场（一种矢量光场）,研究了多色部分相干径向偏振光场经确定性介质的远场散射；2)多色径向偏振光束和电磁随机光束经半软边介质的远场散射，发现多次散射谱开关现象；平面光波经由半硬边介质和多高斯分布介质这两种叠加型介质的弱散射；3)空心双曲正弦高斯光束(HsGB)和可控空心光束(CDHB)的传输、深聚焦及其对瑞利粒子的光场辐射力；4)提出一种通过对反常涡旋光束进行相位调制来产生携带轨道角动量的混合艾里涡旋光束的新方法，产生的混合艾里涡旋光束具有光学涡旋和艾里光束的双重特性；5)提出一种构建可调谐弱啁啾双艾利-贝塞尔涡时空波包的方案，并给出了生成实验装置。生成的高阶波包携带具有复杂结构的光学涡流，并在相当长的距离内呈现传播不变性；6)提出基于空心高斯光束(HGB)和正弦空心光束(SDHB)的光学艾里变换而产生新颖艾里相关光束的方法；7)提出一种在空心高斯光束中嵌入立方相位和轨道角动量生成可控空心艾里-高斯涡旋光束的新方法。总之，该项目研究了几种特殊结构的光场（包括：多色部分相干径向偏振光场、电磁随机光场、平面光波经等光束）经由确定性介质、半软边介质、半硬边介质和多高斯型介质的弱散射，发现了“多光谱开关”、散射“临界角”等有趣现象；研究了空心双曲正弦高斯光束(HsGB)和可控空心光束(CDHB)的传输、深聚焦及其对瑞利粒子的光场辐射力，研究了这几种新型光镊的捕捉特性；另外，在光学艾里变换和特殊时空结构光场的构建及其在手性介质传输方面做了有益探索。研究结果可在拓展光场的散射理论、光场调控、光学微操控，以及构建特殊结构时空光场方面获得应用。